package two;

import java.util.Scanner;

public class test11085 {
    public static int[] array;

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int n = scanner.nextInt();
        array = new int[n * 2 + 1];
        System.out.println(f(2 * n));
    }

    private static int f(int m) {
        if (array[m] != 0) {
            return array[m];
        }
        int k = m / 2;
        int sum = 0;
        if (m == 0) {
            return 1;
        }
        for (int i = 1; i <= k; i++) {
            sum = f(2 * i - 2) * f(m - 2 * i) + sum;
        }
        array[m] = sum;
        return sum;
    }
}
